[ Enhancement ] Consider allowing users accounts to be auto-provisioned

[gwright99]

This configuration snippet allows accounts to be auto-provisioned if an individual is added to a Workspace but does not yet exist in the Seqera Platform instance:

tower.:
  participant:
    auto-create-user: true

There may be some nuances between Collaborators and Member behaviour.

TO DO: Discuss with Product / Eng before adding to project.